Excavator: Ground. Marikovskaya (1984) describes a nest of H. sajoi which was found on a compacted path on a mountainside. The soil was humus. Near the entrance to the nest, a small mound of excavated spoil was located on one side. The entrance and the initial gently sloping part of the burrow (length of 1.2cm) had a diameter of 4.5-5 mm. Vertically down from the expansion of the burrow branched two cells. One (sealed), with provision and a developing larva, and the second (open), with just an unformed pollen ball. The walls of the cells are polished, with a whitish secretion coating their surface and with subtle longitudinal grooves. The brood cells are 9.5-10mm long with a diameter of 5.5-6mm. The cell entrance is narrowed down to 3.5-4mm. The semi-liquid provision is formed into a ball with a diameter of 4-5 mm. Larvae are located on the side closest to the exit.
According to Grozdanic (1971), this species is primitively eusocial, with colonies increasing in size from July to September, and with the founding gyne somewhat larger than the workers (which appear in the summer). In Kazakhstan, females ranged in size from 9.5 to 12mm.